Process of freeing yeast extracts from bitter principles.



MAX ELB, OF DRESDEN, GERMANY.

PROCESS OF FREIEING YEAST EXTRACTS FROM BITTER PRINCIPLES.

Specification of Letters Patent.

Patented Nov. 14, 1905.

Application filed December 18,1903; Serial No. 186,690.

To aZl who'ln it many concern.

Be it known that I, MAX ELB, a subject of the King of Saxony, and aresident of Dresden, in the Kingdom of Saxony, German Empire, haveinvented a new and useful Process of FreeingYeast Extracts from. BitterPrinci ples, of which the following is an exact specification.

My invention relates to a process of free ing yeast extracts from bitterprinciples by means of which the bitter taste of alimentary yeastextracts (especially extracts of beeryeast) is avoided. Nearly allalimentary yeast extracts have a disturbing bitter aftertaste which isderived partly from the dissolved hop-resins in the cells of the yeastand partly from other alkaloids and bitter principles. In order to freethe yeast extracts from these bitter principles and to obtain a pureyeast extract the extracts are treated according to the presentinvention with a substance which gives off oxygenthat is to say, withoxidizing agents. By this treatment a precipitation of the bitterprinciples takes place most probably in consequence of the saidprinciples becoming resinous, so that the precipitated bitter principlescan be removed by filtration. The treatment with the substances givingoff the oxygen can be carried out both with the clear or somewhatcondensed extract and with the extract which still contains the residueof the yeast-cells. The process may also be carried out afterward afterdissolving the already condensed extract.

For carrying the process into effect nearly all oxidizing agents canbeused as far as these agents do not deleteriously affect the alimentaryqualities of the extract. So, for instance, ozone,oxygenin stemncscendt', superoxids, or the likemay be used. In case of residuesremaining in the solutionas is the case for instance, in using peroxidof manganese or peroxid of barium-these residues must be removed in thewell-known way. It has proved most advantageous to use peroxid ofhydrogen for carrying the process into effect. In using peroxid ofhydrogen the process maybe carried out, for instance, by condensing theyeast extract to half of its volume, then adding the peroxid of hydrogenand boiling the mixture for a short time. The quantity of peroxid ofhydrogen added amounts to about sixty to one hundred cubic centimetersfor one kilogram of perfectly-condensed yeast The resulting precipitatesare very extract.

hard to filter, and it is therefore advantageous to remove the same bymeans of one of the well-known clarifying processes-such as, forinstance, by means of albumen.

Having thusfully described the nature of my invention, what I desire tosecure by Letters Patent of the United States, is-

l. The process for freeing yeast extracts from bitter principles,consisting in condensing the extract, then precipitating the bitterprinciples by treating the condensed extract with oxidizing means, andremoving these principles from the extract, substantially as describedand for the purpose set forth.

The process for freeing yeast extracts from bitter principles,consisting in precipitating the bitter principles by treating the yeastextracts with peroxid of hydrogen and boiling the mixture for a shorttime, and removing these principles from the extract, substantially asdescribed and for the purpose set forth.

The process for freeing yeast extracts from bitter principles,consisting in condensing the yeast extract to half of its volume, thenprecipitating the bitter principles by adding peroxid of hydrogen andboiling the mixture for a short time, and removing these princp'les fromthe extract, substantially as described and for the purpose set forth.

4. The process for freeing yeast extracts from bitter principles,consisting in adding to the yeast extract an oxidizing agent, boilingthe mixture for a short time and then removing the resultingprecipitates, substantially as described and for the purpose set forth.

5. The process for freeing yeast extracts from bitter principles,consisting in precipitating the bitter principles by treating the yeastextracts with an oxidizing agent, and removing the resultingprecipitates by treating the mixture with albumen, substantiallyasdescribed and. for the purpose set forth.

6. The process for freeing yeast extracts from bitter principles,consisting in adding to the yeast extracts from sixty to one hundredcubiccentimeters of peroxid of hydrogen for each kilogram of condensedyeast extract to be manufactured, boiling the mixture and removing theresulting precipitates, substantially as describedv and for the purposeset forth.

7. The process for freeing yeast extracts from bitter principles,consisting in condensing the yeast extract to half of its volume,

then adding from sixty to one hundred cubic i In testimonyiwhereoi? Ihave signed my centimeters of peroxid of hydrogen ior each I name tothis specification 1n the presence of kilogramofperfectly-condensedyeast extract two subscriblng wltnesses.

to be manufactured, boiling the mixture and MAX ELB. 5 removing theresulting precipitates, substan- Witnesses:

stially as described and for the purpose set PAUL E. SOHILLING,

fort

PAUL Alums.

